LG 37LG7000 (CHASSIS:LD88F) Service Manual ▷ View online
- 21 -
2-9. In case of No sound
(1) Symptom
1) LED is green.
2) Screen display but sound is not output.
2) Screen display but sound is not output.
(2) Check the followings
All input(mode) is no sound?
Is the speaker on it menu?
1. Menu > Audio > TV Speaker ON/OFF.
1. Menu > Audio > TV Speaker ON/OFF.
Is the speaker Cable normal?
1. Isn’t damage in the Speaker Cable?
2. Is the Speaker cable connect well form
1. Isn’t damage in the Speaker Cable?
2. Is the Speaker cable connect well form
Main B/D to Speaker.
Only HDMI is No sound?
Download the EDID data.
No
Yes
IC601(Audio AMP) operates Normal?
1. Check 16V input Voltage. (IC600 pin49~52)
2. Check 1.8V input Voltage. (IC600 pin12, 13, 16)
3. Check the IIC communication. (SDA/SCL : R619, R620)
4. Check the Audio Signal is Normal. (SPK_L/R : L603, L604)
1. Check 16V input Voltage. (IC600 pin49~52)
2. Check 1.8V input Voltage. (IC600 pin12, 13, 16)
3. Check the IIC communication. (SDA/SCL : R619, R620)
4. Check the Audio Signal is Normal. (SPK_L/R : L603, L604)
Yes
Replace Main B/D.
Yes
Yes
Set on speaker in menu.
(TV Speaker OFF -> ON)
(TV Speaker OFF -> ON)
No
Change or Reconnect
the Speaker Cable.
the Speaker Cable.
No
Replace Audio
AMP IC(IC600).
AMP IC(IC600).
No
Yes
Only RF is no sound?
Check the Tuner IN/OUT
SIF : R317, SECAM-L : R326
SIF : R317, SECAM-L : R326
Yes
No
No
Only AV/component/PC
input is no sound?
input is no sound?
Replace Main B/D.
Check the Input Sound IN/OUT
AV1 (R : JK100 pin2 and C679
AV1 (R : JK100 pin2 and C679
L : JK100 pin6 and C692)
AV2 (R : JK101 pin2 and C690
L : JK101 pin2 and C690)
AV3 (R : JK103 pin7 and C616
L : JK103 pin8 and C615)
PC
(PC_LIN : 635, PC_LIN : R634)
Component
(R: JK102 pin3E and C614
L : JK102 pin5D and C613)
No
Yes
2-10. In case of no connection blue tooth device
(1) Symptom
1) TV set display is fine.
2) TV set don’t search blue Tooth device.
2) TV set don’t search blue Tooth device.
(2) Check the followings
- 22 -
Check the blue tooth device power.
Recharge device and power on
The blue tooth device is headset?
Check connection blue tooth cable on TV set.
Yes
No
No
No problem
No problem
No problem
Is it Pairing Mode?
(Blue tooth headset device)
Check P903(main board) 5pin(5V).
Replace IC904 of Main B/D
Or Replace Main B/D
Yes
Yes
Setting headset to ‘Pairing Mode’ and retry
Check P903(main board) 2,3pin signal
USB interface
Replace Blue Tooth board.
No
No signal
- 23 -
BLOCK DIAGRAM
1. Main
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- 24 -
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Control Bus
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203
2. FRC
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